From 2D layer to 2D → 3D parallel interpenetration: Syntheses, structures and luminescent properties

Two new coordination polymers based on 1,1’-(1,4-butanediyl)bis(imidazole) (bbi) and 5-hydroxyisophthalic acid (OH-BDC), [Co₂(HO-BDC)₂(bbi)₂]·H₂O (1) and [Zn(HO-BDC)(bbi)] (2), have been hydrothermally synthesized. The complexes were characterized by single crystal X-ray diffraction, IR and elemental analysis. The structure determination reveals that 1 manifests a deeply corrugated 2D layer with a (4,4) lattice. For 2, there is a highly undulating 2D (4,4) layer structure. The layers penetrate by each other to give a 2D → 3D parallel interpenetrating network. Fluorescence properties and thermal stabilities of 1 and 2 in the solid state have been studied.